1. Field of the Invention
This invention relates to the field of identifying tools or instruments as belonging to a group or set. In particular, the invention relates to a method of identifying sets of medical or surgical instruments. Further, the invention relates to an instrument bearing indicia of a set to which it belongs.
2. Description of the Prior Art
Surgical instruments are gathered into sets which are kept separately in an operating room. With each instrument assigned to a particular set, it is easier to account for all instruments at any given time.
In the past, operating room personnel have resorted to placing colored, vinyl adhesive tape on the handles of particular instruments to identify them as belonging to a given set. However, surgical instruments are repeatedly sterilized in steam autoclaves. A standard autoclave treatment may exceed 15 minutes where the autoclave is first purged of air with steam and then the contents heated with steam at 121.degree. C. The colored vinyl tape breaks free over time. It is apparently altered by repeated autoclaving. The vinyl tape that remains on the surgical handles gradually chips away due to occasional impacts when instruments are tossed onto a gathering table after use. The vinyl tape identifying also prevents total sterilization of surgical instruments. It may protect bacterial growth therebeneath from sterilization by the autoclaving process. (Interestingly enough, it is not simply the temperature treatment of the autoclaving that destroys the bacteria, but rather the combination of temperature and steam in the absence of air.)
Recently, surgical instrument sets have been introduced with handles that are specially painted to color code the instruments which belong to a given set. The process of painting the handles is understood to be very expensive, to assure that the paint is secured to surgical instruments which are made from stainless steel.
It is not known how durable the painted surgical instruments will be since they have only recently been introduced to the market. However, it is believed that the paint, like the vinyl tape, being in the form of a thin, colored film, is vulnerable to being chipped away over time. Painting is of little use to previously purchased surgical instrument sets. Since the painting process is so special, it is not possible to easily retrofit older instrument sets with painted handles.
It is known in the art that certain utensils can be made from autoclavable elastomers. For example, U.S. Pat. No. 4,253,830 teaches the use of autoclavable plastics in dental bur blocks having color-coded receptacles in which dental drills, grinders and the like can be inserted for cleaning. However, the purpose of these color-coded plastic receptacles is for holding the tools to be autoclaved. The identification means disclosed therein does not permanently attach to the respective instruments belonging to a set.
In U.S. Pat. Nos. 3,747,603, 3,935,640 and 4,202,351, color-coded medical instruments are disclosed but for different purposes. In both U.S. Pat. No. 3,747,603 and No. 4,202,351, the same instrument in each set of instruments is uniformly colored. The color coding does not identify members as belonging to a set but rather is used to identify the size of the synthetic, surgical dilator in U.S. Pat. No. 3,747,603 and the terminal function of lead wires to electrocardiogram monitoring equipment in U.S. Pat. No. 4,202,351. In U.S. Pat. No. 3,935,640, color coding of an area of a dental instrument is taught for determining the depth of insertion of the tip to a periodontal probe. None of the above patents, alone or in combination, teach or suggest the method of identifying instruments and instrument bearing indicia of belonging to a set.